http://revach.net/article.php?id=2844

Section:  Avodah   Category: Tshuva
Rabbeinu Yonah Reasons For Tshuva - Reason 3: Without Ears You Are Worthless
Through your ears you can leave behind the dark and enter the light in the bat of an eye.  When a person hears mussar and takes it to heart, deciding that he will change it is if he already has changed.  A person must change from hearing mussar or else he will be punished.  Before punishing Klal Yisroel, Hashem always sent Nevi'im to warn them.  Only if the ears are sealed shut does Hashem punish.

It says in Avos D'Rav Nosson that a person whose  ma'asim,deeds are more than his chochma, wisdom, his chochma will last.  How can a person have more deeds than wisdom, asks Rabbeinu Yonah?  If he does not know what to do, he cannot do it.  He answers that the moment a person makes up his mind to do whatever he will be told, it is as if he already did it even without knowing what it is that he must do.  This is the secret of Na'asehV'Nishma.  Since they agreed to do anything Hashem asked, it is considered done before even knowing the task required.

All this through the ears.  it is no wonder, says Rabbeinu Yonah, that if you damage any limb in the body, you pay for the limb.  However if you damage a person's ability to hear, you pay his entire worth.  A person that doesn't or cannot listen cannot improve.  If so, he is worthless.